Configuring new deliciated HA heartbeat for Redundancy.

Hello Expert,

I have two 400E in a HA cluster .

We use the default HA ports for Heartbeat interface but had to add redundancy using the lan port.(BR_DATA port8) After reviewing numerous documentation we found that this was not best practice since the lan port is heavy use for data.

I would like to assigned a new deliciated port (24)  to be my  backup heartbeat and remove (BR_DATA (port8) but would need some guidance since this is a production environment. 

Also to configure port 24 as heartbeat port are there any special configuration need prior to it being assigned .

GuyOffice-1 (ha) # show
config system ha
set group-name "trans_amt"
set mode a-p
set password g==????Swdee
set hbdev "ha" 200 "port8" 100
set session-pickup enable
set override disable
set priority 200
set monitor "port8"
end

Thank you